The use of catalytic fluidized bed reactors is known in processes of chemical engineering.
Also known is the placement of an aspiration tube in the chamber of a fluidized bed reactor, to promote the circulation of the solid species within the reactor (ICFB reactors).
Likewise known is the combination of the catalytic reactor with a regenerator disposed adjacent to it, and the establishment of a spent catalyst stream from the reactor to the regenerator, and of a regenerated catalyst stream from the regenerator to the reactor. Systems of this kind are appropriate when the deactivation of the catalyst is relatively rapid (typically over a period of the order of a few seconds or minutes) and the catalyst requires frequent regeneration. These systems are used in particular for the conversion of hydrocarbons to oxygen-containing olefins. Examples of these systems are provided by documents U.S. Pat. No. 6,437,208, US 2007/0203383, and US 2010/0028224.
The Zhang et al. article titled Hydrodynamics of a novel biomass autothermal fast pyrolysis reactor: flow pattern and pressure drop, in Chem. Eng. Technol. 32:27-37 (2009), describes a reactor for the catalytic pyrolysis of biomass, in which the pyrolysis is carried out in a central part, with entrainment of biomass and of catalyst, while the deposits on the catalyst are burnt in a peripheral zone of the reactor. This reactor design, however, is not suitable for reactions where the residence time of the catalyst in the reaction zone has to be relatively high (of the order of several hours, for example) for the purpose of optimum efficiency.
The catalytic fluidized bed reactors of the prior art are not suitable for allowing effective control of the reaction gas flow rate independently from the stream of catalyst for regeneration, or for effectively providing the regenerator with heat, in order to optimize the implementation of chemical reactions in the gas phase (U.S. Pat. Nos. 4,623,443; 3,057,923; US 2003/073751; U.S. Pat. No. 2,872,472; EP 340 852).
At the present time there is no facility that is sufficiently compact and allows optimum control of the operating conditions, especially for reactions in which the deactivation of the catalyst has a characteristic duration with an order of magnitude of greater than a minute and less than a month.